This invention relates generally to writing instruments in which ink or other writing fluid flows through a capillary element and, more particularly, to a means for preventing movement or retraction of the capillary element into the barrel of the writing instrument when subjected to writing pressures.
Writing instruments having a tubular barrel, an internal ink reservoir and a capillary plastic or fiber nib through which ink is transferred from the reservoir to a writing surface are well known in the art. The nibs are typically held in place by crimping or deforming the ferrule portion of the barrel onto the nib. Oftentimes, a separate nib holder is utilized, the nib holder being inserted into a seat at the open end of the barrel. The nib holder is staked or dimpled to hold the nib so that it will not be pushed into the barrel while in use. The staking or dimpling must be sufficient to properly hold the nib, but cannot be too deep so as to disrupt the capillary flow through the minute capillary conduits of the nib. Because of the small dimensions involved with such assemblies, the degree of dimpling or staking was heretofore critical. If the nib was not adequately staked, the nib would often push up into the nib holder preventing further writing; if the nib was staked too deep, the flow of ink through the capillary conduits of the nib was often blocked or partially blocked which interfered with a writing operation.
It is therefore highly desirable to find a convenient and inexpensive means for holding such small capillary nibs in firm writing position without interfering with the capillarity of the nibs.